The donor-acceptor copolymer containing benzothiadiazole (electron acceptor), linked to functionalized fluorene (electron donor), [poly[9,9-bis(3'-(tert-butyl propanoate))fluorene-co-4,7-(2,1,3-benzothiadiazole)] (LaPPS40), was synthesized through the Suzuki route. The polymer was characterized by scanning electron microscopy, gel permeation chromatography, NMR, thermal analysis, cyclic voltammetry, X-ray photoelectron spectroscopy, UV-vis spectrometry, and photophysical measurements. Theoretical calculations (density functional theory and semiempirical methodologies) used to simulate the geometry of some oligomers and the dipole moments of molecular orbitals involved were in excellent agreement with experimental results. Using such data, the higher energy absorption band was attributed to the π-π* (S(0) → S(4)) transition of the fluorene units and the lower lying band was attributed to the intramolecular (ICT) (S(0) → S(1)) charge transfer between acceptor (benzothiadiazole) and donor groups (fluorene) (D-A structure). The ICT character of this band was confirmed by its solvatochromic properties using solvents with different dielectric properties, and this behavior could be well described by the Lippert-Mataga equation. To explain the solvatochromic behavior, both the magnitude and orientation of the dipole moments in the electronic ground state and in the excited state were analyzed using the theoretical data. According to these data, the change in magnitude of the dipole moments was very small for both transitions but the spatial orientation changed remarkably for the lower energy band ascribed to the ICT band.
Este trabalho analisa a trajetória do Programa de Pós-graduação em Formação Científica, Educacional e Tecnológica (PPGFCET) da Universidade Tecnológica Federal do Paraná (UTFPR), perante a perspectiva da epistemologia de Ludwik Fleck. A partir da reestruturação da Lei de Diretrizes e Bases de 1996, da criação da área de Ensino de Ciências e Matemática, do Programa de Reestruturação e Expansão das Universidades Federais e outros documentos oficiais e programas governamentais, é observado quais os pressupostos e características dos círculos esotéricos e exotéricos, com os seus respectivos coletivos de pensamentos, bem como a transferência de conhecimentos intra e intercoletiva que culminaram na criação e desenvolvimento do programa. Verifica-se que o programa demonstra estar de acordo com as mudanças propostas na educação brasileira, sendo necessários às demandas sociais, e que está alinhado com a circulação de conhecimento de Fleck, respeitando as características do processo de criação científica. Constata-se também que a interdisciplinaridade é um elemento comum e necessário tanto para a perspectiva de Fleck quanto para os documentos oficiais.
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